关于android：从上次连接的WIFI中获取WIFI ID

WifiManager mainWifi = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
WifiInfo currentWifi = mainWifi.getConnectionInfo();

int id = currentWifi.getNetworkId();

public class NetworkReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        ConnectivityManager connMgr =
                (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();

        // Checks the user prefs and the network connection. Based on the result, decides
        // whether
        // to refresh the display or keep the current display.
        // If the userpref is Wi-Fi only, checks to see if the device has a Wi-Fi connection.
        if (WIFI.equals(sPref) && networkInfo != null
                && networkInfo.getType() == ConnectivityManager.TYPE_WIFI) {
            // If device has its Wi-Fi connection, sets refreshDisplay
            // to true. This causes the display to be refreshed when the user
            // returns to the app.